With the development of the mobile Internet and smart devices, higher requirements are put forward for a capacity of a wireless network. Measures taken in a traditional capacity expansion solution mainly include adding a carrier for a system, adding a site, or the like. The cost of the traditional capacity expansion solution is excessively high due to limited network spectrum resources, a great difficulty in site acquisition, and a high cost of launching a new site.
A coverage area of a base station is generally determined by a coverage area of a signal sent by a base station antenna. A traditional sector refers to a sector area covered by a beam transmitted by a base station antenna. Referring to FIG. 1, a coverage area of a base station including 3 antennas is generally divided into 3 traditional sectors.
In a case where no site or carrier is added, in order to implement capacity expansion of a wireless network, a sector splitting technology is generally used for splitting a traditional sector with a high capacity requirement into a plurality of sectors, so that the number of sectors of a base station is increased and more carriers are allocated within coverage areas of the additional sectors. The increase in the number of carriers enables a base station to serve more user equipments. Therefore, the traditional sector splitting technology can implement capacity expansion of a wireless network with a low cost. However, in the traditional sector splitting technology, because each sector obtained by splitting is planned as a cell, a coverage area of a cell corresponding to a sector is greatly reduced. Therefore, signal interference between the cells is aggravated, which affects the handover and accessibility performance, and the like of a wireless network and increases the complexity of network planning and optimization.
FIG. 2 is a schematic diagram of 6 sectors obtained by splitting 3 traditional sectors in a multi-sector cell networking technology, in which two smaller sectors obtained by splitting a same traditional sector are separated by a dotted line. In the multi-sector cell networking technology, the two smaller sectors obtained by splitting the same traditional sector share a same cell identity and send same pilot signals and same common channel information. That is, in the multi-sector cell networking technology, the two smaller sectors obtained by splitting the same traditional sector together form a cell.
In the multi-sector cell networking technology, control channel information is sent in a joint transmission manner, that is, a base station transmits the control channel information to a user equipment simultaneously in all sectors of a cell in which the user equipment is located. FIG. 3 is a schematic diagram of using the multi-sector cell networking technology to send control channel information in the case of virtual 6-sector. User 0 and user 1 are two user equipments, and cell 0, cell 1, and cell 2 are three cells of a same base station. User 0 is located in sector 00 of cell 0, and user 1 is located in sector 01 of cell 0. A frequency domain location f0 is used by a control channel of user 0, and a frequency domain location f1 is used by a control channel of user 1. Control channel information is sent to a same user equipment through left and right sectors of cell 0 simultaneously, for example, control channel information is sent to user 0 in frequency domain location f0, or control channel information is sent to user 1 in frequency domain location f1.
In FIG. 3, in joint transmission, when control channel information is sent to user 1 through sector 01 of cell 0, the control channel information is also sent to user 1 through sector 00 of cell 0. Therefore, cell 2 is interfered with by a signal sent in sector 00 of cell 0. That is, although sector 00 in cell 0 is not adjacent to cell 2, when a signal is sent to user equipment user 1 through sector 00 of cell 0, cell 2 is still interfered with by the signal. Similarly, in joint transmission, when a signal is sent to user 0 through sector 00 of cell 0, the signal is also sent to user 0 through sector 01 of cell 0. Therefore, cell 1 is interfered with by the signal sent in sector 01 of cell 0. That is, although sector 01 in cell 0 is not adjacent to cell 1, when a signal is sent to user equipment user 0 through sector 01 of cell 0, cell 1 is still interfered with by the signal.